The "net metering" rule expands a requirement for investor-owned utilities to buy back electricity from people who produce it from renewable resources.
"These are some of the most important policies Florida can enact if we are going to grow renewable energy industries in Florida," said Holly Binns, field director for the group Environment Florida.
The rule does not apply to electric cooperatives or utilities owned by cities and counties.
But some of those utilities, including Tallahassee's city-owned utility, already pay their customers for producing renewable energy.
The Legislature in 2005 and 2006 adopted laws encouraging the use of renewable energy in Florida. Environmentalists at a January 2007 workshop told the PSC that limits on net metering were major barriers to producing cleaner energy.
The PSC rule expands the size of eligible systems from 10 kilowatts, which is about the size of solar panels that would go on a home, to 2 megawatts, which is the size of solar panels that could go on an office building or big box store, said Kirsten Olsen, a PSC spokeswoman. The rule change also expands the type of systems covered from solely photovoltaic to all renewable technologies.
Some farmers are considering taking advantage of the rule by producing electricity by burning methane gas produced from cattle waste, said Andrew Walmsley, environmental services coordinator for the Florida Farm Bureau Federation. But there also are challenges, he said, because the technology is expensive and more research is needed.